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Year 3 Mental Addition and Subtraction Strategies Worksheet — Level 3 — Practice Set 4 — Answers

Answer sheet with worked solutions for the Year 3 addition worksheet.

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Success TutoringWorksheetsAnswer sheetYear 3 · Mathematics · Addition

Year 3 Mental Addition and Subtraction Strategies Worksheet — Level 3 — Practice Set 4 — Answers

Fill in each step of the strategy, then write the answer.

1.163 + 59 = 163 + 60 − (answer space) = (answer space)

Answer: 1, 222

  1. 163 + 60 = 223
  2. 223 − 1 = 222
2.176 − 99 = 176 − 100 + (answer space) = (answer space)

Answer: 1, 77

  1. 176 − 100 = 76
  2. I took away 1 too many, so add it back: 76 + 1 = 77
3.141 − 6 = 141 − 1 − (answer space) = (answer space)

Answer: 5, 135

  1. 141 − 1 = 140 (back to a ten)
  2. 140 − 5 = 135
4.126 + 98 = 126 + 100 − (answer space) = (answer space)

Answer: 2, 224

  1. 126 + 100 = 226
  2. 226 − 2 = 224
5.63 − 29 = 63 − 30 + (answer space) = (answer space)

Answer: 1, 34

  1. 63 − 30 = 33
  2. I took away 1 too many, so add it back: 33 + 1 = 34
6.64 − 6 = 64 − 4 − (answer space) = (answer space)

Answer: 2, 58

  1. 64 − 4 = 60 (back to a ten)
  2. 60 − 2 = 58
7.102 + 28 = 102 + 30 − (answer space) = (answer space)

Answer: 2, 130

  1. 102 + 30 = 132
  2. 132 − 2 = 130
8.159 − 59 = 159 − 60 + (answer space) = (answer space)

Answer: 1, 100

  1. 159 − 60 = 99
  2. I took away 1 too many, so add it back: 99 + 1 = 100
9.102 − 5 = 102 − 2 − (answer space) = (answer space)

Answer: 3, 97

  1. 102 − 2 = 100 (back to a ten)
  2. 100 − 3 = 97
10.40 + 49 = 40 + 50 − (answer space) = (answer space)

Answer: 1, 89

  1. 40 + 50 = 90
  2. 90 − 1 = 89
11.79 − 38 = 79 − 40 + (answer space) = (answer space)

Answer: 2, 41

  1. 79 − 40 = 39
  2. I took away 2 too many, so add it back: 39 + 2 = 41
12.43 − 6 = 43 − 3 − (answer space) = (answer space)

Answer: 3, 37

  1. 43 − 3 = 40 (back to a ten)
  2. 40 − 3 = 37
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